Improves unknown command handling

[cgranleese-r7]

This PR improves the handling of unknown commands within console. Additionally this works for Meterpreter and the new session types - MySQL/PostgreSQL/MSSQL/SMB.

Currently when users get a command wrong, they are given the following error:

Unknown command: reloa

We now tell users to use the help command, and also suggest a potentially close match if one exists.

Scenario when we have a suggestion:

Unknown command: reloa. Did you mean reload? Run the help command for more details.

Scenario when we do not have a suggestion:

Unknown command: foo. Run the help command for more details.

Example:
Console top level:

Meterpreter:

SMB session type:

Verification

• Start msfconsole
• Run the help command.
• Verify that commands listed in the help command work with the new command handling
• Verify that the expected output is returned when there is a suggestion present as well as not
• Verify this also works within Meterpreter and the new session types. Use the help command to see what commands can be ran

[dwelch-r7]

Release Notes

Improves unknown command handling by suggesting similar valid commands